Edition: BP 2025 (Ph. Eur. 11.6 update)
Aluminium Acetate Ear Drops
General Notices
DEFINITION
| Aluminium Sulfate | 225 g |
| Calcium Carbonate | 100 g |
| Tartaric Acid | 45 g |
| Acetic Acid (33%) | 250 mL |
| Purified Water | 750 mL |
Extemporaneous preparation
The following directions apply.
Dissolve the Aluminium Sulfate in 600 mL of the Purified Water, add the Acetic Acid and then the Calcium Carbonate mixed with the remainder of the Purified Water and allow to stand for not less than 24 hours in a cool place, stirring occasionally. Filter, add the Tartaric Acid to the filtrate and mix.
The ear drops comply with the requirements stated under Ear Preparations and with the following requirements.
Content of aluminium, Al
1.7 to 1.9% w/v.
CHARACTERISTICS
A clear liquid.
Weight per mL
1.06 to 1.08 g, Appendix V G.
ASSAY
Dilute 10 mL to 100 mL with water. To 10 mL of the resulting solution add 40 mL of 0.05M disodium edetate VS, 90 mL of water and 0.15 mL of methyl red solution. Neutralise by the drop wise addition of 1M sodium hydroxide and warm on a water bath for 30 minutes. Cool, add 1 mL of 2M nitric acid and 5 g of hexamine and titrate with 0.05M lead nitrate VS using 0.5 mL of xylenol orange solution as indicator. Each mL of 0.05M disodium edetate VS is equivalent to 1.349 mg of Al.
STORAGE
Aluminium Acetate Ear Drops should be kept in a well-filled container.
When aluminium acetate solution or Burow’s Solution is prescribed or demanded a solution complying with the requirements of this monograph shall be dispensed or supplied.
